He qualified in Medicine in Leeds in 1995, and started working with children two years later. He trained in and around Yorkshire before moving to London for Registrar training in 2000. He completed an Masters in Clinical Paediatrics in 2003. He was appointed as Clinical Lecturer at University College London, contributing to research into the molecular genetics of infantile hypertrophic pyloric stenosis and furthering his interest in Medical Education by contributing to the design, delivery and assessment of 4th Year Medical Students at University College London (UCL) Medical School. He has continued his links there and for nearly 10 years was lead for the undergraduate Paediatric attachment at Watford General Hospital for medical students from UCL's Medcial School, where he has been nominated as Distinguished and Top Teacher consistently. Between October 2015 and March 2020 he was the Undergraduate Tutor at Watford General Hospital overseeing senior UCL  Medical Student attachments. From April 2020 he has been been appointed the Associate Medical Director for Medical Education.

In 2009 he was awarded an Excellence in Medical Education award from UCL. He has been an Honorary Senior Clinical Lecturer In Paediatrics at University College London. He is a Fellow of the Higher Education Academy and of the Academy of Medical Educators. He completed a Postgraduate Certificate in Medical Education in 2009, and in 2016 graduated with distinction in a Masters in Medical Education from the University of Bedfordshire.

He is a Fellow of the Royal College of Paediatrics and Child Health and is an Examiner for their postgraduate examinations. In 2010 he was asked to examine Paediatricians in Egypt and ran a 'Teaching the Teachers' Education Course for Egyptian doctors while in Cairo. He co-organised the National Paediatric Educators' Programme, an education course for UK Paediatricians, for the Royal College of Paediatrics and Child Health from 2010 to 2015.

From 2012 to 2016 he was Chair of the START Assessment Board, the end of training assessment run by the paediatric Royal College. In July 2016 he was appointed the Officer of Assessment at RCPCH.

He is widely published on aspects of clinical paediatrics and education. In 2008 he published an article about the inappropriate use of flat cola in children with gastroenteritis (diarrhoea and vomiting). The paper received world-wide press and media attention (click here for more information).

Ashley lives in Pinner where he is very involved with his local community. He is married with a daughter and a poodle.